This project focuses on the study of tissue, surface and small airway properties of whole lungs, and on lung/chest wall interactions in whole animals. In the coming year studies are planned to : (a) examine effects of temperature, pH and osmolarity on tissue recoil; (b) measure subphase pH and buffering capacity using alveolar washes; (c) determine the basis of apparent changes aggregation depending on state of hydration of the subphase; (d) elucidate fluid absorption via pleura into interstium and subphase; (e) make mechanical measurements on excised guinea pig lungs; (f) determine interfacial tension between various oils and alveolar fluid and plasma, and to explore the possibility of inflating the vascular bed (including capillaries) with oil, and altering recoil of alveoli by filling with a series of oils.